Abstract: In a brushless motor, the number of coreless armature coils is set to 3n when the number of magnetic poles of a magnet for a magnetic field is set to 2n where n is a positive integer. An opening angle of each of the armature coils is set to 360/3n degrees. A notch portion is formed in an outer circumferential portion of the magnet for a magnetic field. A recessed portion is formed by this notch portion and an inner circumferential portion of a yoke. The recessed portion constitutes a groove for correcting a balance of each of the magnet for a magnetic field and a rotating body when this magnet and the rotating body are rotated. A motor housing and a harness are electrically connected to a printed board. The housing is connected to the ground through this harness and a harness for power. In this brushless motor, a magnetizing frequency is reduced and driving efficiency of a control circuit can improved when the brushless motor is rotated at a high speed.

Abstract: A thermal printer comprising a line type thermal head which is arranged substantially in parallel with the shaft of a platen and is swingably supported about the longitudinal central portion thereof can obtain clear printed letters and prevent the abrasion of the platen due to the direct contact between the thermal head and the platen even if the recording paper varies in width or thickness or is set on the platen one-sided. To achieve the above object, members for restricting the swinging of the thermal head are prodded at both end portions thereof, one of the members being adjustable in its restricting position and the thermal head is supported by a head supporting means composed of a head plate, a head frame and tension springs so as to be movable toward or away from the platen so that the thermal head is separated from the platen according to the thickness of the recording paper and does; not contact the platen.

Abstract: In a thermal printer for performing printing on the printing surface of a tag which is drawn out from a tag roll and then held and conveyed by a platen and a line thermal head, the thermal printer comprises a thread sweeping means for sweeping away the threads which get on the printing surface of the tag and a tag guide means disposed downstream the conveying direction of the tag for bringing into contact with the side edge of the tag which is opposite to the other side edge thereof to which the threads are attached so that the threads which get on the printing surface of the tag are swept away by the thread sweeping means and the tag is conveyed in the manner that the threads do not contact the tag guide, which eventually prevents the threads from being caught by parts on the conveying route or prevents the tag from being printed on the printing surface thereof while the threads remain getting on the printing surface.